1. Field of the Invention
The present invention relates to an oil deterioration suppressing apparatus, and more particularly to an oil deterioration suppressing apparatus capable of enhancing a trapping effect of an oil deteriorating component and capable of reducing oil-flow resistance and restraining a pressure loss from increasing.
2. Description of Related Art
As a conventional filter element, there are known a filter element made of particles (e.g., hydrotalcite and the like) and fiber for removing carbon, acid, deteriorated materials and the like generated in an internal combustion engine (for example, see Related Art 1). In an oil filter using this filter element, as shown in FIG. 15 for example, a housing 102 in which a filter element 110 is accommodated is provided with an oil inflow passage 107 through which oil sent from an oil pan flows into the housing 102, and an oil outflow passage 108 through which oil filtered by the filter element 110 flows out to portions of an engine to be lubricated (e.g., crankshaft, cylinder wall, valve gear, etc.). Oil which flows into the housing 102 from the oil inflow passage 107 is filtered by the filter element 110, carbon and the like are removed by particles 115, and the oil flows out from the oil outflow passage 108 into a lubricating portion of the engine.
There is known a filter using a filtering material obtained by heating and forming an adhesive fiber processing material and a material for a filtering material containing sepiolite (for example, see Related Art 2). This filter has an excellent trapping effect of oiliness impurity component by using together with sepiolite, and is suitable for lubricating automobile engine.    [Related Art 1] JP-A 03-296408    [Related Art 2] JP-A 2001-38119
According to the conventional oil filter described in the Related Art 1, however, since all of oil sent from the oil pan passes through the filter element (so-called, fullflow filtration), particles such as hydrotalcite configuring the filter element become resistance and there is a problem that a pressure loss increases. According to the filter described in the Related Art 2, the trapping effect is merely evaluated using test oil containing specific test dust including carbon black, ferric oxide, and the like. In this document, a trapping effect of other deterioration components is not verified. Further, the sepiolite has a problem that a trapping effect of nitric ester which is one kind of deteriorated material of engine oil is small.